About 3,400 grunting animals live in two giant barns, separated into 14-foot-square pens, 25 animals in each.

An electric timer delivers scientifically formulated grain from overhead plastic pipes at regular intervals. Automatic "nipple feeders" let pigs drink when they want. Their manure falls - or is tramped - through slits in the concrete floor into giant, concrete-lined "lagoons" beneath the barns. "It's so automatic, there isn't much I need to do," said Hickory Lane's owner, Ricky Leese, 53, here in southcentral Pennsylvania's Belfast Township, where there are 10 pigs for every person.

Big hog farms like this are becoming more common in Pennsylvania - the number has doubled to 190 in the last decade - and they are now spawning environmental, agricultural, and legal battles across the state.

Owners of big farms - and the corporations who pay them to raise the animals - say the operations are clean, modern and efficient, meeting a growing consumer demand for pork.

Opponents call them "factory farms," and say they mean nothing short of environmental disaster.

Now, competing lawyers from the Philadelphia suburbs and Washington are preparing to descend on a small county courthouse to fight a test case over whether communities have the power to ban the big farms.

It's a debate that has raged for years in North Carolina and Iowa, where farms of 100,000 pigs exist. Now it's in Pennsylvania. (New Jersey has no large pig farms; its only large animal-feeding operations are two chicken farms.)

Critics of the big-farm operations include Philadelphia restaurateurs, environmental activists, neighbors of the big farms, and owners of small ones. They say the manure from large farms can harm rivers and streams pointing to notorious spills in North Carolina - and claim that the big barns are inhumane breeding grounds for disease.

"I don't like the way they treat the animals," said Ian Dietrich, who works on his parents' small Cumberland County, Pa., dairy farm and keeps 11 pigs of his own. "I don't like the conditions for the farmer. I don't like the . . . potential to damage the water supply. I don't like the amount of antibiotics they use to keep the animals alive."

Supporters counter that the big barns are state-of-the-art - sometimes even monitoring the animal's air and water by computer - and insist that Pennsylvania's laws are rigorous enough to prevent problems.

"A human being may look at this and say, 'Boy, I wouldn't want to live like that,' " said James L. Adams, president of PennAg Industries Association, a farm-industry trade group. "But if the animals were getting sick all the time, or they weren't growing right, we wouldn't pen them that way."

Adams said the system is designed to get the most meat to America's dinner tables with the highest quality, the most consistency and the least cost.

"It's driven by the consumers," Adams said. "Whether they know it or not, they vote every day by the dollars they use."

The nature of farming is changing in Pennsylvania For now the attention is focused on Belfast Township, here in the rolling hills of south-central Pennsylvania.

Many communities have attempted to restrict the size or activities of the big farms - officially called "concentrated animal feeding operations" - but have had little success because of the state's permissive zoning laws.

Belfast, with the help of the Chambersburg-based Community Environmental Legal Defense Fund, is one of nine municipalities trying a new tack: prohibiting corporate involvement in farms.

Leese and three other local farmers have challenged the Belfast restrictions in a lawsuit. PennAg views the suit as an important test case and is paying the farmers' legal bills.

One of the township's three measures says corporations, with "fewer reasons to respect the natural environment . . . than do natural persons," may not "engage in farming." Existing corporate-operated, -financed or -owned farms would be permitted to continue under the ordinances.

The township says it is acting in the public interest by protecting family farms from being squeezed out of business by corporations.

The farm industry says the township has no legal right to regulate farm ownership, and that the ordinances unfairly discriminate against corporations. The corporations say that by guaranteeing farmers a steady paycheck, they are helping them stay in business.

The legal debate aside, at least one thing is not in dispute: The nature of farming is changing in Pennsylvania - and fast.

Take hogs. The number of farms in the state with more than 2,000 hogs has nearly doubled to 190 in the past decade - with some housing 15,000 or more pigs - while the number of farms with fewer than 100 hogs has fallen by more than half.

The animals on the big farms aren't owned by the farmers, but by agri-corporations, which pay farmers about $10 a head to raise a pig from 15-pound piglet to 250-pound hog.

Raising and marketing pigs is now governed by complex contracts between feed companies, meat packers, and farmers. Many traditional markets, such as the one in Chambersburg where a farmer would auction off a few pigs at a time, have closed.

Instead, most pigs head straight from mega-barn to packing plant, traveling in tri-level tractor-trailers.

In Belfast Township, the issue has pitted neighbor against neighbor.

"They don't do a thing for the area. They don't put anyone to work. They don't even buy their feed here," deli owner Gene Mellott, 64, said of the big farms. "We have enough farms around here making enough stink as it is."

Leese, a Pennsylvania State University graduate who uses "bio-security" to describe steps the industry takes to prevent disease, said the concerns of people like Mellott are unfounded.

"I've always considered myself pretty much of an environmentalist," he said, noting that he recycles his manure by hiring a company to spray it on his 600 acres of oats, hay, wheat and corn twice a year.

Are the farms bad for the environment? There's little dispute that they can be, if improperly managed.

Pennsylvania law requires farms above a certain size and density to file a "nutrient management plan" - describing how they will dispose of manure and how they will keep it from entering streams. If farmers don't have enough land to accommodate the waste, they must arrange for it to be taken elsewhere.

The Susquehanna River Basin Commission, which monitors water quality in the area where most of the state's large-scale farms are located, has not seen any farm-related decline in the river's health over the past decade.

But the group conducts most of its measurements on the main stem of the Susquehanna. Officials say if the big farms were causing problems, there aren't enough of them to make a difference in such a big river - yet.

Big-farm opponents say it's only a matter of time before there are more incidents like one that happened in April 1998.

That's when a Cumberland County farmer's manure spreader got stuck near a tributary of the Yellow Breeches Creek, a popular trout stream.

To get unstuck, he dumped 5,000 gallons of hog manure onto the ground, state officials said. Much of the manure ended up in the stream, killing most of the fish. A local road-crew employee said at the time that the stream water "looked like oil you drain out of your car."

Small-farm owners, firms ready for a lengthy battle State officials reported last year that 2,887 miles of Pennsylvania streams are "impaired" by agriculture, though the report did not distinguish between small farms and those with corporate involvement.

Farmers such as Leese say the big farms with ties to well-financed corporations are better equipped to meet the rigorous environmental regulations. In addition, they say, big farms are efficient, keeping prices down in supermarkets.

And there is clearly a demand: Pennsylvanians eat an estimated 600 million pounds of pork a year - 50 pounds for every person in the state.

Though the number of big farms has grown, the number of hogs in the state has remained constant at about one million over the last decade.

Environmentalists say the concentration of animals exacerbates problems such as odor, manure leakage, and disease.

Factory farms use more water than the traditional "free-range" farm model. The two sides disagree on how much more the big farms use, but there's no dispute that water is needed to hose down the barn floors and to turn manure into a solution that can be sprayed onto fields.

"Once you get hog lagoons that are holding two or three million gallons of watered-down hog slurry, it starts to become a huge problem," said Jan Jarrett, director of outreach for PennFuture, an environmental group in Harrisburg.

The farms have led some Philadelphia-area restaurant owners and grocers to find other sources of meat.

"When I heard about them, I was just mortified," said Judy Wicks, owner of the White Dog Cafe on Sansom Street. Her solution: Create the Philadelphia Fair Food Project, a group of two dozen area restaurants that buy meat from smaller, traditional farms, where animals spend at least some of their time outdoors.

Meanwhile, the courtroom battle over Belfast's ordinances is gathering steam.

A hearing is expected in the next six months, when a lot of out-of-town lawyers will arrive at the red-brick courthouse in nearby McConnellsburg - so small it doesn't have a full-time judge.

The farmers are represented by Stevens & Lee, a 180-member firm with offices in Philadelphia, central Pennsylvania, South Jersey and Delaware. The township is being represented for free by Arnold & Porter, a Washington law firm with more than 700 attorneys.

"We decided if they were going to come in with a Philadelphia law firm, we were going to come back with one of the largest law firms in the nation," said Tom Linzey, executive director of the Community Environmental Legal Defense Fund that helped Belfast and other communities with their ordinances.

He predicted a long, drawn-out battle.

"This case will eventually end up in the Pennsylvania Supreme Court, from one side or the other," Linzey said. "It'll be three to four years getting there."